A. Technical Field
The present invention relates to security applications in digital electronics and, more particularly, to systems, devices, and methods of encrypting digital logic gates.
B. Background of the Invention
Methods to reverse engineer physical IP are becoming increasingly powerful, automatable, and affordable. Today, sophisticated attackers can gain access to and reverse engineer secret encryption and decryption keys embedded in hardware without much effort. A complete, annotated, hierarchical netlist of a digital circuit can be obtained for less than $15,000. This includes circuits that cannot be patented or otherwise protected—exposing proprietary information. This creates a number of severe problems to chip manufacturers and their customers. A related problem is the exposure of keys due to theft and unauthorized distribution of devices. For example, a subcontractor might sell excess quantities of a manufactured device to others, or resell substandard devices that failed to conform to the contractor's manufacturing specifications under an alternate trade name.
As a consequence, manufacturers are forced to expend considerable time and money to develop countermeasures to deter adversaries. Numerous methods to encrypt, obfuscate, and hide information have been employed in the software domain for a long time. Until now, however, no equivalent methods have been feasible in the hardware domain. Nor does there exist any generation of hardware that would be capable of implementing such techniques.
What is needed are effective systems and methods that allow for the protection of valuable IP and information in the hardware domain, ideally, using automated procedures that are compatible with existing manufacturing tools and processes.